I am using a power source to charge a battery. To protect the power supply from reverse polarity conection of battery I included a PMOSFET transistor like showed:
The problem is that this only works when power supply if off. If the power supply is on, so transistor conduces like VGS < Vt, and if now battery is connected with reverse polarity (VBAT < 0) there is a large current flow from source to battery like a short circuit, due to the large voltage diference between V1 and VBAT, and the transistor still conduces.
Is there some way to avoid this problem?